Just off Piazza Mercato, the Museo del Coltello Sardo is dedicated to the ancient Sardinian art of knife-making. The museum was founded by Paolo Pusceddu, whose s'arburesi (from Arbus) knives are among the most prized on the island. Check out Signor Pusceddu's historic knife collection and, in the entrance courtyard, one of the world's largest penknives.